If I'm understanding the schema, every "virtual" screen is build by 16*12 4x4 tiles, isn't it?. And you show only the map window under the player position...If the scroll is always a character one (8 pixels), how can it be implemented to match the 2:1 ratio(x:y) speeds?

the map motion is continuous (2x1 pixels virtually, ( int(x/8),int(y/8) for the display, in that text 8x8 mode ) for displaying in text mode) , but the sprite position is always interfering with the map display - that's why i'm not thinking about using 2x1 characters (i have not the 'exact' or close algorithm for this yet...)

about the map, the bottom 32x64 blocks are continuous, and the upper 32x16 is looping

here is a sketch i did on sdlBasic - i used the whole map in a picture (which is not clean enough, as well i didn't correct the 8x1 colour cell limit) - the pictures are in bmp format because they compress better on 7zip (bz2 compression)

this sketch explains better the idea i have about it - the original scroll algorithm from Sammy is a bit more complex (on my version, if you move back the ship, the scroll simply freezes, and on original version doesn't - and some other more stuff i really can't understand how to get that else working)

btw, even if the result of this remake would be frustrating, this algorithm can be an idea to do similar games (for example, i think there is a similar game coded to x86 computers at early 90's ( 92 or 93, i think), but i can't recall how is it named... (i think it has stuff like alpha-multilayers (semi-transparent), and more impressive enemies motion cadences ))

Hey nitro!, nice to read you again! Yep, indeed it looks cool (although youtube blurries a bit the demo). Have you keep trying with Z80 assembler?, I'm not talking about a project like Viewpoint (no easy at all); but some more humble ones just to practice.

hi, jltursan!I got a small pause in the msx development a bit - maybe seeking for other sinergic references could help to pursue trying to develop up-to-now unique stuff on msx, which i (and we all?) think as very welcome in the msx retrocoding scene...

latelly i were posting some videos at youtube - http://youtube.com/user/nitturo - mostly for promoting the sdlbasic as open-source basic interpreter, since i were somehow involved in the development team - and so, sdlBasic were a kind of interesting way to test some ideas i'd like to see working on msx! :-)

and what i think as an interesting game on a msx1 were like this one, using those 3d anagram red/green glasses (please try if you have available, or you can make one with those transparent papers, hard paper, glue, scissors, etc... :-) - you may find some diy instructions at google if needed... ) :http://www.youtube.com/watch?v=xv6_50rugcUperfectly possible to be made on a msx1 (afaik) - since all colour attribute area is predefined before, only working on the bitmap area - the problem is coding this with my humble knowledge about z80/msx asm

about 4 player sprite moving, i think i posted here in the snippets area, but i think it got lost when moving now to msxgamesbox server... - of course i'd love to develop better about z80 coding! :-)

before i forgot: since 1 year ago, i'm only using Linux now (and MacOS-X very rarelly) - do you know good z80/msx compilers for Linux? - good idea is if Robsy port his asmsx compiler to Linux as well (and if he decide to make it gpl, who knows being part of the official debian/ubuntu repositories...)